


Mosaic

by BlueDysania



Category: Undertale (Video Game)
Genre: Abusive Relationships, Angst with a Happy Ending, Emotional Hurt/Comfort, Implied/Referenced Past Underage Oral Sex, Kedgeup is Safe Sane and Consensual, M/M, Panic Attacks, Past Abuse, Past Gaslighting, Sans (Undertale) Needs a Hug, Very Mild Brief Reference
Language: English
Status: In-Progress
Published: 2019-07-23
Updated: 2019-09-26
Packaged: 2020-07-11 14:30:03
Rating: Mature
Warnings: Creator Chose Not To Use Archive Warnings
Chapters: 2
Words: 3,517
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/19929601
Author URL: https://archiveofourown.org/users/BlueDysania/pseuds/BlueDysania
Summary: Boristen returns to Snowdin years after he'd left his hometown. He expects everything to be as it always was in the sleepy, snowy town. And expects Sans to be the same exquisitely shattered mess he'd made the skeleton into all those years ago.But time moves on and the town is certainly not the same as it was before. In particular, a pair of brothers now live there and Boristen is in for a rude awakening.





	1. Old Town

**Author's Note:**

> there is an OC but the main focus here is Sans and Edge (Kedgeup). :3

Boristen knew he'd reached Snowdin when he entered an area covered in a light dusting of snow. It sparkled in the bright, summer light, and he turned on the heat in his car to prepare for the dip in temperature the closer he got.

It was a relief to finally get here. Snowdin was a far distance from the capital of New Home. Boristen smirked to himself as glanced in his rear-view mirror as if he could still see the impressive city and the young reindeer gal he'd left behind. It had been the most fun he'd had in a while. Souls desperate for love and stupid enough to get caught in his grasp were harder to find out of high school. Still… he'd bled Noelle's kind Soul dry for a good year, turning the successful college student on her way to a doctorate or some shit into a timid creature that didn't know whether to attend class or skip it when he _asked her nicely_ too.

And it had been a challenge to dodge that aggressive lizard bitch stalking through the campus. The year had been entertaining as hell until Noelle decided to spring some unexpected news in his face.

A snort of disgust left him as he recalled her teary eyes and whimpering voice telling him that she was pregnant. As if he'd want to be responsible for some scrawny brat that would cry all night and day. Dumping her right then and there had been easy. Boristen was an expert at dropping his wreckage and moving on.

Let the Komodo have at it, all Susie would get is a ruined girl with a broken heart and some extra baggage growing in her.

Still, Boristen had been a little annoyed at needing to move out of the capital. Noelle had been a little more well-connected than he guessed. Discovering that his boss, Gyftrot, was a friend of Noelle's family meant that he'd been fired on the spot the next day. And it wasn't like he could continue going to college with the rampaging Komodo and her posse on the look out for him. The goat and the young nephew of one of the Professors' were harmless enough, but the mute human was fucking creepy.

Snowdin only made sense in the end. Return to his hometown and maybe visit an old friend. And an old experiment. Boristen's finest destruction in his opinion.

His experiments were always successful even if ones like Noelle were cut short. Still, he always met his goal. Getting monsters to fall in love with him, carefully cultivate devotion and use it to break them down into shells of their former selves. Then once they are perfectly ruined throw them away and find another one.

Sans Serif however… that had been a masterpiece. The perfect age, the perfect setting… everything had been perfect.

Sans had been one of Snowdin High School's brightest students. Smart, an easy but eager temperament with a goofy, fun personality all tied together with a few scholarships and steady placement on Honor Roll. And a Soul full of compassion.

Usually, Boristen stayed away from classmates in the spotlight but something about Sans' demeanor had lured him in. The dark part of him he'd been sustaining with bottom feeders' anguish wanted to destroy Sans Serif.

Perhaps it was the puns that rankled on his every nerve for how stupid and horrible they were. Perhaps it was some self-insecurity from all the smart talk he exchanged with the teachers, even ones he didn't have as instructors. Maybe it was the way some moneyless orphan with no standing to speak of should be accepted into every crowd in the school.

Boristen did know what sealed Sans' fate. What had pushed him over the edge was the sheer audacity Sans had displayed when they'd been assigned as lab partners. Correcting and arguing and stealing the lead position when the teacher agreed with Sans' observations.

Fury at being upstaged by such a small bag of bones, he'd smiled and congratulated Sans for his insight. Sans, oblivious fool that he was, took the olive branch and didn't realize it was rotten. Everything spiraled from there.

After Boristen had gotten done with him Sans was no longer acing every class. Scholarships unfinished and all but failing his classes. Friends and family unable to help him because Sans had been twisted and turned until he was tripping over himself to make Boristen happy. And so very desperate to keep his love.

That meant no more puns; he hadn’t laughed at a single one, even the ones that were a little bit funny. No more science babble; derisive comments and put-downs about how stupid it was and that Sans probably wasn’t smart enough to get very far had stopped the skeleton from bringing it up again. And no more disagreements; after Sans was on his metaphorical leash all he had to do was hint that he might be looking at someone else and Sans shut his mouth.

It was beautiful to even remember it.

Sans had even continued to defend him when he was found ineligible for graduation. When the well-laid plans to be an intern at the prestigious _Royal Science Laboratories_ fell through. It was his fault, Sans said over and over, he just didn’t work hard enough. _Sans_ wasn’t good enough.

Boristen still felt a perverse satisfaction at how he'd left. Without a word and without warning. He'd just left with his own diploma in hand and knowing that Sans was still confidently ~~desperately~~ trying to convince everyone that Boristen would never leave him; Boristen _loved_ him.

He'd left Sans an empty-socketed mess with little will to stand for anything he believed in anymore. A beautiful shattered mosaic and he hoped Sans was just as he left him. Or worse. Boristen grinned, gripping the steering wheel with delight at the thought. He could swoop in and convince Sans to love him all over again. He needed a place to sleep and some food anyway. It had been a long time but Boristen was sure his idea would come to fruition.

After all, how could anyone love what he'd made Sans into?

This would be the first time in five years he would step foot into his hometown.

He couldn't _wait_.

* * *

Boristen's first stop was an old friend from high school. Using social media, he pins down Doggo's work place and lies in wait outside of it. When he sees Doggo exiting the pastel colored building, he puts on a friendly face and swaggers over.

"Well, well!" He calls out and doesn't miss the way that Doggo stiffens and then turns around slowly like he's reluctant to acknowledge him. "If it isn't my old friend! How ya doing, Doggo?"

Doggo finally faces him and Boristen notices almost immediately the scar over one of his eyes. He thinks about asking how Doggo got them but then shrugs it off. It's not like he cares and obviously Doggo is fine now.

"Uh, hey. Boris. You're back?"

"You don't sound too excited." Boristen said deliberately, smile turning a bit more sympathetic. Best grease the wheels a bit, after all. "Didn't want me to know you're stuck working at the nursery school? What are you, a janitor or something there?"

Doggo's ears fell slightly and he shuffled his feet, moving back a step, "Teacher’s Assistant."

Boristen crossed the small distance and patted Doggo on the shoulder, then wrapped his arm around him and started to lead him away toward a pub he’s missed for all these years, "That's _horrible._ But don't worry. We'll get you into something cool once I settle in."

Then he'd have Doggo back under his thumb too. His old friend would be so grateful that he'd helped him get out of working with slobbering, noisy ankle-biters that he'd be following him around like old times. Boristen nodded to himself, feeling his plans coming together perfectly.

Doggo had been instrumental in helping him to isolate and tear down his toys' confidence. He couldn't have done so much in so little time without Doggo running interference. It would be good to have a little back-up again.

"You're planning on staying?" Doggo asked slowly.

Boristen scoffed, "Have too. Got some dumb broad from the Delta University knocked up. So, I'll be here for now. Or longer, if I can get at Serif again."

Doggo tensed further under his arm and then broke free of the hold on his shoulders. The movement startled Boristen. When had Doggo gotten that strong? Now that he really looked, he saw the muscles rippling under fur and realized at the same time that Doggo was… bigger than he used to be.

"Sans?" Doggo asked, frowning, "Sans Serif?"

"Who else? His obnoxious little brother?" Boristen laughed bitterly. Oh, he'd resented Papyrus for a very long time. The one thing that Sans had backbone for had been for his little brother. He'd driven a weak wedge between them but it never lasted. A bond not easily broken and as far as he knew remained that way. "Serif is still in town, right?"

Doggo said nothing and was looking around uneasily. Boristen rolled his eyes and tugged at Doggo's arm to get them walking again.

"Come on, man. I'm hungry and out of cash. Treat an old friend, would you?"


	2. Snooper

**Notes for the Chapter:**

> Warnings at Bottom!

Seated in the fast food joint, Boristen wolfed down his burger and fries. Free food was always the best. He knew he could count on Doggo, even if he was acting weird. He peered over his meal at Doggo. The canine was fiddling with the straw of his drink, the only thing he purchased. Besides Boristen's meal. Doggo seemed on edge about something but had been silent since he'd wheedled a free meal out of his wallet.

Boristen had just swallowed the last bite of his burger and grabbed his shake when Doggo spoke again.

"Sans is already in a relationship."

The words weren't whispered or hard to understand. They just didn't make sense. His toys didn't recover from his work. Okay, _maybe_ they did but they weren't very good merchandise; and Sans? Sans, his masterpiece of ruin, was in a relationship? That… that…

That was _hilarious_ and Boristen guffawed around the fries he stuck in his mouth. Doggo watched him with wide eyes and it only made him laugh more.

"Oh! Oh, that is hysterical!" Boristen had to drink some more of his shake to clear his throat and then continued, "Who's the unlucky sap who took pity on him? Should give him a medal!" banging the table with a fist.

Doggo's eyes got wider and again, he looked around the entire joint's lobby. Boristen rolled his eyes. The lobby was basically empty! There might have been a little mouse with a ridiculously large scarf and some strange lanky, grinning red monster in another booth peeking over at them but _whatever_.

Doggo leaned in to hiss, "Boris, I'm not kidding. He's with someone and it's pretty serious."

"Yeah." Boristen scoffed, smirking widely, "Well, we'll see about that. Sans was… _is_ obsessed with me, remember? Once he sees me, we'll see just how ' _serious_ ' this ' _relationship_ ' is." Air quoting the words with his greasy fingers. "Besides, I need some place to crash and I'm sure whatever shack Serif has managed to get will do for now."

"Boristen." The grave tone was the only thing that made him look up, some age-old and long-ignored instinct prickling at the back of his mind to pay attention. "You… We were… friends. I can't stop you. But I'm begging you. Don't try to do… whatever it is you are going to do to Sans. His mate." Doggo shuddered and rubbed at his snout, "He's powerful. And _dangerous_. You don't want to mess with him.”

Doggo paused and his ears fell flat, a soft whine issuing as he finished, "And… And Sans is _kind_."

Boristen sat back and took in the warnings from his old friend in silence. Then once he was sure Doggo was finished, he grinned. Meanly. "Good to know you turned into a bitch, Doggo. Bet you had a hard-on for Serif the whole time too, didn't you? All those bones? _Oh, don't hurt him Boris, he's kind_." He mocked.

Doggo looked stricken, and sick, "No-!"

"I don't care who this guy is." Boristen snapped, "Serif is a wreck and you can't tell me some tall, dark, and dangerous stranger has swooped in for him. He's not worth the attention. Now, I'm gonna go and find my _old flame_ ,” He said sarcastically, standing and wiping his hands on some napkins before throwing them in Doggo’s direction, “See you later… or not.” He snorted, sauntering toward the door.

It would have been nice to have an obedient associate around to give him a hand. But in reality, he didn’t need anyone.

He located a cheap motel, good enough until he could secure his free ride, and rented the cheapest room. Stashing his bags, he popped open one of the complimentary drinks and took a swig. Now that he had a place to sleep, he decided to see if Doggo’s ridiculous claims held any water. Fiction and fact and all that shit.

He crushed the aluminum and ignoring the dribbles that stained the bedsheets, smirked to himself. Time to do some snooping.

A week later, Boristen was _not_ happy.

It had started out pretty good. The day after swindling Doggo out of a meal, he’d hit the streets. Nostalgia lasted all of a couple hours before the changes of the small snowy town became noticeable. For one, the graffiti that had painted alleyways and low-income stores was completely gone. He’d had a hand in a few pieces of spray-painted art, signing his name all over town, and to see it gone was disappointing.

In fact, most places in town looked newly painted, cracked windows now pristine, and shiny new locks installed on every business’ doors. The trash in the streets, while it hadn’t been out of hand all those years ago, was almost non-existent now.

Boristen had sat down for a while, completely floored by the new vibe of his hometown. Snowdin hadn’t been any more unsafe or trodden down than other towns. It had been pretty average. But there _had_ been evidence of crime and unsavory behavior from break-ins to littering.

Now, the fresh snow wasn’t the only thing sparkling.

It was… disconcerting for some reason.

Maybe it was due to the fact there were more guardsmen roaming the town than he remembered. Boristen had one or two break-ins to his name that he’d never been found out for and while he’d strutted his escape from punishment before, there was something to the new guard force that had him ducking his head at times.

He didn’t recognize any of their faces for one. Asking around, he discovered that the ol’ Guard Lieutenant had finally crossed the line when evidence of taking bribes from drug dealers was discovered. He was convicted and a new Lieutenant brought in to clean up the former one’s mess. Part of that was either firing incompetent guardsmen or sending them for retraining in Waterfall’s Royal Guard HQ.

This Lieutenant, a real hard-ass in Boristen’s opinion, had been a storm of change.

Instead of damage though, the sleepy town was doing better than ever and everyone Boristen talked to, even people who _complained_ about him, all had this admiring tone of voice or wry smile on their faces.

The Lieutenant wasn’t all sunshine and roses. He had a very low-tolerance policy for any misdemeanor, big or small. And he didn’t play nice when it came to rooting out criminals. Oh, he acted in accordance of the law, but he didn’t pull his punches and had no qualms of getting his hands dirty to get things done.

And Snowdin seemed to love him for it. It showed in the sense of tranquility that everyone glided in.

He’d yet to see the monster in question yet, but his opinion on the Lieutenant was already low on principal. He had an image in his head of some pompous monster in a uniform but wielding his power like a club. Sure, he was doing some civil good, but Boristen bet it was all a cover or some shit for any wrong-doings he was doing under the table.

But that was just the town and Boristen could have shrugged all the newness away if that was the only thing that had differed from his expectations.

He’d also asked around about Sans. Not too overtly of course. He played up the _just passing through_ card, wanting to see some old acquaintances before he moved on, etc.. He couldn’t be sure anyone remembered him and avoided a few monsters he knew might, such as the school grounds and their faculty.

All the same, he got strange looks from a few vendors and the one time he waltzed into a pub, with a _mute_ bartender of all things, he’d gotten nothing but an icy stare in return. Not even the patrons, sensing the owner’s mood perhaps, were all too interested in talking to him.

And he kept seeing those _damn_ kids, the scarf rat and devil looking one all over the place too! He’d spied them talking in an alley to a shady character in a black jacket, the hood and yellow faux fur hiding his face from view. He’d snorted at the sight and walked on. Some work the Lieutenant was doing if two kids could be talking to an _obvious_ drug dealer in broad daylight without anyone reporting it.

Despite the roadblocks, he managed to scrape together the story during his years away from Snowdin.

Sans had been exactly what Boristen thought he would be. An absolute wreck of a monster. He’d dropped out of school and all but disappeared from the public eye until his father, a mysteriously absent monster Boristen never bothered to learn about, had apparently gotten him into some expensive therapy.

Every other day sessions became weekly sessions over the years but Sans had been well-known around town for his listless and shabby demeanor. Unemployed, no diploma, and with the inability to function in normal society. If Sans had still been in that limbo of a state, Boristen knew his plan would have been easily accomplished.

Throw out a lifeline. Oh, Sans, he regretted his decision all these years, don’t you still _love_ me, and Sans would be wrapped around his finger hook, line, and sinker.

Except that wasn’t how it was anymore. And he learned the Lieutenant’s name.

Two years ago, Edge Aster, came to Snowdin. And he did more than repair just the town.

At some point, Edge and Sans had crossed paths and though it was unclear when it started the two were clearly dating now. Sans was apparently doing a lot better for it; Edge providing some sort of support that was doing the depressed skeleton good. A few sources said it was getting pretty serious too.

Sans had moved into his own apartment, no longer living with his brother. He had gotten a job at a little botanist shop where he took commissions for floral arrangements as well as sold normal bouquets; a job acquired at the recommendation of his therapist. He was beginning to live a relatively normal life with a small circle of close friends, one of those a bartender and owner of the local pub… which explained a few things.

Boristen had to go back to his hotel room to process all of the information he’d gathered… and he was disgusted. All of that work tearing Sans apart and this is what he gets? Some hotshot guardsmen moving in on his turf and trying to ‘fix’ what he’d broken?

“Bullshit…” Boristen huffed and laid back. Well, that was fine. All he had to do was reintroduce himself. He’d show that fucking guard what Sans really was, a desperate soul who’d do anything to hear someone say ‘ _I love you_.’ And if the guardsmen really was the double-faced monster Boristen figured he had to be, he’d get Sans back without a fight to boot. An offer to share ‘ _the_ _goods’_ would be no hardship and he’d get a foothold against the local law.

A filthy grin stretched across his face.

Now that Sans was older, that meant he could finally have a different kind of fun with him. If he’d known beforehand that skeletons couldn’t make the right parts until after a certain age, he’d have… well… done the same thing but at least he wouldn’t have to just make do with a throat and tongue this time around.

He’d track down the flower shop tomorrow and see if he could find a time when Sans was there alone. He didn’t want any interruptions for their reunion. He couldn’t _wait_ to see the lovely despair in Sans’ eyes again.

Boristen fell asleep quickly that night, dreaming of all the things he was planning to do to ruin Sans life for a second time.

**Notes for the Chapter:**

> *Reference to two teenagers having oral sex in high school.


End file.
